Let's get to the huge ferry disaster. A ship packed with high school students on an overnight trip to a popular tourist destination in South Korea. It sank so fast. And terry Moran has the latest on the search for survivors. Terry? Reporter: Good morning, George. This is a desperate situation. And it is ongoing. It was supposed to be a trip to paradise. 325 high school students, their teachers, other crew members and passengers en route to the resort island of jeju, the Korean Hawaii, it's called. Then, disaster struck. Desperate scenes off the coast of South Korea. Frantic efforts to rescue passengers from the stricken ferry, including hundreds of high school kids. More than 100 vessels and aircraft came to help. Then, a horrible sight. The ferry sinks. Almost 300 remain missing. Young survivors describe the chaos. The announcement told us we should stay still, this student who scrambled to safety said. But the ship was already sinking. And there were a lot of students who did not get out of the ship. Many passengers were at breakfast. Others, still in bed. When survivors say they heard a loud crash. And the ship began shaking and immediately listing. It was very intense, this survivor recalled. The ship was tilted more than 45 degrees. Anxious relatives gather at the school where the youngsters were students. Now, a scene of dread and fear and weeping. Survivors say many people may have remain trapped inside the ship when it sank in murky waters off the Korean mainland. Divers Aring looking inside the wreckage. And helicopters and rescue boats are scouring the scene, looking for anyone who may have left the doomed ship. No one knows what caused that collision everybody felt. But survivors are pointing to one possible problem onboard the ship. They were told to stay in place. That may have been a terrible mistake. And the ship went down quickly in a couple of hours. Give us a scope of the rescue operation right now. Reporter: It is vast. It's right off the coast of South Korea. And there are hundreds of ships and vessels involved. 87 ships, lots of helicopters. Divers in the water. The problem is, the water is about 54 degrees fahrenheit. Survivors have a couple hours before hypothermia sets in. That's a scary situation. Thank you very much. Now, details coming in on

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